infra/modules/nsg/nsg_apim.tf

resource "azurerm_network_security_group" "nsg_apim" {
  name                = var.nsg_apim_name
  location            = var.location
  resource_group_name = var.resource_group_name

  # External Only
  security_rule {
    name                       = "allowanyhttpsinbound"
    priority                   = 100
    direction                  = "Inbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_range     = "443"
    source_address_prefix      = "Internet"
    destination_address_prefix = "VirtualNetwork"
  }

  security_rule {
    name                       = "management-endpoint"
    priority                   = 200
    direction                  = "Inbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_range     = "3443"
    source_address_prefix      = "ApiManagement"
    destination_address_prefix = "VirtualNetwork"
  }

  security_rule {
    name                       = "load-balancer"
    priority                   = 210
    direction                  = "Inbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_range     = "6390"
    source_address_prefix      = "AzureLoadBalancer"
    destination_address_prefix = "VirtualNetwork"
  }

  security_rule {
    name                       = "traffic-manager"
    priority                   = 220
    direction                  = "Inbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_range     = "443"
    source_address_prefix      = "AzureTrafficManager"
    destination_address_prefix = "VirtualNetwork"
  }

  security_rule {
    name                       = "dependency-on-storage"
    priority                   = 100
    direction                  = "Outbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_range     = "443"
    source_address_prefix      = "VirtualNetwork"
    destination_address_prefix = "Storage"
  }

  security_rule {
    name                       = "dependency-on-sql"
    priority                   = 200
    direction                  = "Outbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_range     = "1433"
    source_address_prefix      = "VirtualNetwork"
    destination_address_prefix = "SQL"
  }

  security_rule {
    name                       = "dependency-on-kv"
    priority                   = 300
    direction                  = "Outbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_range     = "443"
    source_address_prefix      = "VirtualNetwork"
    destination_address_prefix = "AzureKeyVault"
  }

  security_rule {
    name                       = "publish-diagnostcs"
    priority                   = 400
    direction                  = "Outbound"
    access                     = "Allow"
    protocol                   = "Tcp"
    source_port_range          = "*"
    destination_port_ranges    = ["1886", "443"]
    source_address_prefix      = "VirtualNetwork"
    destination_address_prefix = "AzureMonitor"
  }
}

resource "azurerm_subnet_network_security_group_association" "nsg_apim_association" {
  subnet_id                 = var.apim_subnet_id
  network_security_group_id = azurerm_network_security_group.nsg_apim.id
}